Jewel

$ tldr Ruby on Rails deser (CVE-2020-8165) → oathtool 2FA → sudo gem

·	·
Operating system	Linux
Difficulty	Medium
Vector	Web
IP	`10.10.10.211`
Retirement date	2021-02-13
Skills	Gitweb Enumeration Information Leakage Cracking Hashes Searching for vulnerabilities in Ruby on Rails with Brakeman Deserialization Attack (CVE-2020-8165) - Rails < 5.2.3.4 [RCE] Creating a new application with Rails Creating the payload with Ruby console Abusing Google Authentication (oathtool) Abusing sudoers privilege (gem command) [Privilege Escalation]

Writeups

Language	Author	Format	Link
🇪🇸 ES	S4vitar	Vídeo	Open
🇬🇧 EN	0xdf	Texto	Open
🇬🇧 EN	IppSec	Vídeo	Open

Curated documentation for each technique listed in the Skills column above. Sources: HackTricks, GTFOBins, PortSwigger, etc.

Skill	Source	Link
Information Leakage	HackTricks	Open
Cracking Hashes (hashcat / John)	HackTricks	Open
Insecure Deserialization	PortSwigger	Open
Remote Code Execution (RCE)	HackTricks	Open

Brute Force / Rate-Limit Bypass · Local File Inclusion (LFI) · Remote File Inclusion (RFI) · Shellshock (CVE-2014-6271)

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Last updated: 2026-07-27